The Discrete Self-Adjoint Dirac Systems of General Type: Explicit Solutions of Direct and Inverse Problems, Asymptotics of Verblunsky-Type Coefficients and the Stability of Solving of the Inverse Problem

We consider discrete self-adjoint Dirac systems determined by the potentials (sequences) $\{C_k\}$ such that the matrices $C_k$ are positive definite and $j$-unitary, where $j$ is a diagonal $m\times m$ matrix which has $m_1$ entries $1$ and $m_2$ entries $–1$ ($m_1+m_2=m$) on the main diagonal. We...

Full description

Saved in:
Bibliographic Details
Date:2018
Main Authors: Roitberg, Inna, Sakhnovich, Alexander
Format: Article
Language:English
Published: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна Національної академії наук України 2018
Subjects:
Online Access:https://jmag.ilt.kharkiv.ua/index.php/jmag/article/view/jm14-0532e
Tags: Add Tag
No Tags, Be the first to tag this record!
Journal Title:Journal of Mathematical Physics, Analysis, Geometry

Institution

Journal of Mathematical Physics, Analysis, Geometry
Description
Summary:We consider discrete self-adjoint Dirac systems determined by the potentials (sequences) $\{C_k\}$ such that the matrices $C_k$ are positive definite and $j$-unitary, where $j$ is a diagonal $m\times m$ matrix which has $m_1$ entries $1$ and $m_2$ entries $–1$ ($m_1+m_2=m$) on the main diagonal. We construct systems with the rational Weyl functions and explicitly solve the inverse problem to recover systems from the contractive rational Weyl functions. Moreover, we study the stability of this procedure. The matrices $C_k$ (in the potentials) are the so-called Halmos extensions of the Verblunsky-type coefficients $\rho_k$. We show that in the case of the contractive rational Weyl functions the coefficients $\rho_k$ tend to zero and the matrices $C_k$ tend to the identity matrix $I_m$. Mathematics Subject Classification: 34B20, 39A12, 39A30, 47A57.